Hi folks, welcome to my thoughts on training as an older athlete with some aortic issues!
My situation. Just imagine the danger of flexing my leg (lifting my knee) too much, which is an issue on the bike, potentially yanking on my stent extension.
The real trick to training with a health challenge is to understand your condition, modify your activity for the better (safer) as best you can, and get on with that which you enjoy, as safely as possible.
I’m going to use my situation, the issue of cycling with an abdominal aortic aneurysm stent graft extension into the external and internal iliac (hypogastric) arteries as an example. You have to work out how to apply this kind of approach to your personal situation, as we are all different, but I’m always happy to help anyone if I can.
A little trigonometry with ballpark numbers (using a ruler on my leg) makes one think – a mathematical model would be better, but no time now.
Why think? Think before you leap (or pedal) is my motto, if there’s time that is, or trust your instincts, Blink and go! This is your call, but I wouldn’t totally trust my instincts in a situation where I have time to work out the critical details. I prefer to analyze my biomechanics, especially for the bike, modify my activity accordingly, and then proceed with training as risk-free as possible. In the case of the bike, my goal is to reduce hip flexion (raise my knees as little as possible) at the top of the pedal stroke. This turns out to be an intriguing puzzle. So I start by thinking and analyzing.
Why Collect Data? You can generate data using theoretical (mathematical) and laboratory methods, so I first carried out some simple calculations, more to get me thinking about the details than anything. Using a well know trig equation (see adjacent figure), I concluded that modifying crank length could reduce that key hip angle significantly, especially if combined with dropping my heels at the top of the stroke – can my tibialis anterior muscles handle that? Guess I’ll give it a try. I can also add raising my seat height and standing on the bike as much as I can handle.
Rough numbers derived from simple trig indicated significant potential benefits of crank length and foot displacement – standing on the bike not included.
I’ll sure have to ride differently, but I stand to reduce that critical hip angle, and thus the mechanical risk to my stent extension, by as much as 20% or more. Fortunately, my dentist/triathlete son, Nigel, informed me that Cobb make a 145 mm. crank, so I’m going to give them a try. Lots to think about. When it comes to laboratory data, I’ll be seeking (a) measurements of hip angle on my bike once the 145 mm. cranks are installed, and (b) x-ray measurements of stent extension displacement in relation to hip flexion, which will require collaborations with my surgeon at the Cleveland Clinic and other experts. I’ll keep you posted on lab work!
Why assess benefit/over risk? You can assess your level of risk versus benefit purely intuitively, or apply a more rigorous method. I prefer the latter, having described one approach to this complex question in a previous blog post.
My goal is to provide you with a framework for resolving your training challenges in order that you may take control of your life, and hopefully return to your favorite sport safely. That’s my plan.
It’s your life. How much effort is it worth to you?
Rock on as safely as you can, I say!
-k @FitOldDog
Happy New Year Kevin,
I love your artwork. Did you give the name to your original grant? Why Rupert? Did you know it is a pejorative given by soldiers to the officer class in the British Army?
I asked my son who is a triathlete with one Ironman and quite a few halves under his belt about short cranks. After he got past the opportunity for a cheap short (I’m neither short nor a crank!) he suggested I look at recumbents as a possible source. Now I didn’t find that much, but you might find http://www.recumbents.com/wisil/misc/crank_angle.asp a useful start. I note they talk about 110mm cranks being viable. Good luck.
Rgds, Glenn
PS All that trig brings back memories of when I faile my engineering degree back in the early 70s and reminds me of why I switched to becoming a lawyer:).
Hi Glenn, Rupert was a favorite cartoon story character of mine as a kid, and I wasn’t aware of the pejorative implications. Thanks for the crank source suggestion – I’ll try 145s and see how that goes, and if it might work I’ll consider 110s. Math is good for one’s brain, but I left my math obsession far behind when I hit a brick wall, Topology – it still comes in useful from time to time, however. Lawyer? What do you think of Grisham’s books and my thoughts on Plavix?
Cheers,
kevin
Good approach actually. Then, can you be time competitive modifying the bike procedure, standing more, more wind resistance, etc. What fun you’ll have!
Fun! You should see what their saying on SlowTwitch: http://forum.slowtwitch.com/gforum.cgi?post=4916768;sb=post_latest_reply;so=ASC;forum_view=forum_view_collapsed;;page=unread#unread